Keep pulling the thread on Geoffrey Hinton.
Geoffrey Hinton and Terry Sejnowski proposed using Hopfield-style nets to construct interpretations of sensory input, rather than for storing memories.
The goal of learning in a Boltzmann machine is to adjust its weights so that the images it generates in a 'dreaming' state resemble the real images it is trained on.
A simple learning algorithm for Boltzmann machines was discovered by Geoffrey Hinton and Terry Sejnowski in 1983.
The Boltzmann machine learning algorithm, on average, performs gradient ascent on the log-likelihood of the data.
A major drawback of Boltzmann machines is that the process of settling to thermal equilibrium is very slow, especially for large networks with large weights.
A much faster learning algorithm for Boltzmann machines is possible by restricting the architecture so that hidden units are not connected to each other, creating a Restricted Boltzmann Machine.
Netflix used Restricted Boltzmann Machines, combined with other methods, as part of its movie recommendation system.
A system combining Restricted Boltzmann Machines with other methods won the Netflix Prize competition for predicting user movie preferences.
Initializing a deep neural network by pre-training with a stack of Restricted Boltzmann Machines allows it to learn much faster and generalize better than initializing with random weights.
In 2009, Geoffrey Hinton's students George Dahl and Abdulrahman Mohamed demonstrated that pre-training with stacked RBMs slightly outperformed state-of-the-art techniques for speech phoneme recognition.
In 2012, Google put speech recognition systems based on stacked Restricted Boltzmann Machines into production, significantly improving performance on the Android platform.
Restricted Boltzmann Machines were a crucial innovation that enabled the transition from believing deep neural networks were impractical to demonstrating their effectiveness.